overheating problems (again)

[MrMelon]

I've fully been having the worst luck with this bike over the last month or so... here's a bit of history:

The bike was overheating and using a fair bit of coolant, so it went into the shop where one of the head gaskets was blown, and a power valve wasn't opening, so $370 later I had new head gaskets and my power valves fixed up. I also had the coolant flushed and replaced.

On the ride home it was going really well.... for about 10 minutes then it started misfiring really badly over 6500rpm. I went into the shop and he sold me some new plugs that were 1 heat range hotter than the last ones.. so I changed them over. The old and new ones are just cheap $7 ngk ones though. The ones that were in there that fouled up were BR9ES's and the ones in there now are BR8ES.

Are these cheap plugs shit and could they cause problems? like would a more expensive heat range 9 plug be less likely to foul up than a cheap heat range 9 plug?

Would changing to a hotter plug increase the likelihood of detonation when the engine gets hot? and could it make the engine run much hotter than it should?

Also I went out for a 20km blast tonight, and after 5km of fairly spirited riding aroudn the bays, the temerature started to climb up from it's regular 60-70 deg to 90-100.. a small squirt in 2nd and 3rd would bring the temp from 90 to 100 pretty quickly. when it got hot the engine wasn't feeling as crisp as usual, and up the top of the rev range there was a little bit of hesitation.

All these hassles are starting to get to me, I just want the fucking bike to work properly! :(

[Jackrat]

Sounds to me like it,s just running rich mate.
Have that checked out at a different shop.
I don,t know much about the more moden two strokes,but when I was into them many years ago,I would always start with mixture
first,You might also have your coils an leads checked,
Never give a shop a second chance,at that bloody rate they should get it right.

[gpercivl]

You may need to blow out or clean/replace the air filter...this would give the same richening effect if partially blocked.

B8ES plus are fine, we've been running them in MX in YZ-80 and YZ-125 and as long as you're not doing continuous high speed riding, the slightly hotter plugs will give less 'oiling up'. But, if you do find it is the air filters, I'd go back to the B9's.

[marty]

i had a similar problem in the RS - i discovered that non-resistor plugs had been fitted. put new ones in(admittedly @ $20 each) but what a difference! coolant sits at about 51-54 unless i'm climbing the kaimais hard or stuck behind traffic, which doesn't happen very often.....

the standard for the RS is an NGK BR9

hotter is BR10, cooler BR8. i'm running the BR9.

have u been to your manual and checked what the factory fit is?

[bungbung]

Spirited riding eh MrMelon?, I heard you a while before you passed me (and everyone else) in Evans bay...

nice leathers, match the bike.

[MrMelon]

I'll try and get at the air filters tonight to have a look at them and clean them out. The last plugs I took out were carbon fouled, so I think it might be running a bit rich.

With resistor plugs, you can only use them if you don't have resistor caps right? Is there an easy way to find out if you've got resistor caps or not?

I've tried looking through the manual, but it's all in japanese, so doesn't really help me much :(

Yeah it was just a quick little blast around the bays last night to see how the bike was going and if the leathers fit properly while I was on the bike :D They seem pretty sweet, especially for $550. Once I get this sorted we'll have to go for a ride some time :D

I'm kinda thinking that there might be a small air leak in one of the hoses in the cooling system which is letting air in so the water pump can't circulate the coolant properly, but the guy at the last shop I took it to said that he did a pressure test on the cooling system and it was fine. But I don't really know what else could cause it.

[MrMelon]

If what I can find is correct the ngk BR8ES plugs are already resistor plugs anyway :/

The guy at the shop told me the standard plugs were the BR9ES's

[bungbung]

TZR, does it have an alloy radiator? if you can pull off a pipe to look into the core, you can check to see whether or not the alloy has furred up due to no corrosion inhibitor being used at some point in its past life. Furry internals will inhibit heat transfer from the coolant to the airflow.

[MrMelon]

I don't think it's got an alloy radiator, and when i last looked inside there it seemed fairly clean. It seems more like the coolant isn't being circulated at all.

[madandy]

If you get your mixture set right and it still runs hot maybe your water pump is farked?

[Motu]

I don't know much about watercooled bikes,they were newfangled stuff when I was working on bikes.But I work on watercooled cars everybloodyday.For overheating we go thermostat,fans,blocked radiator,waterpump impellor,ignition timing,lean mixture.

We had a 98 Mondeo last week with a cracked impellor,this is not common,maybe 2 or 3 times a year for me,so is the last thing we think of.Best way to test is to crack a hose,then give her a rev - if you get a squirt of water (dump the coolant and test with water,you can spill and waste it) then you got circulation,no squirt and the pump isn't pumping.

[Dave]

First-NGK plug numbers work in reverse-7 is hotter than 8
8 is hotter than 9.
the spark plug heat range does not make the engine run 'hotter'
or 'colder'. Rather it performs at its best in a chamber in a certain heat range.
That is why our race bikes (125GP) are running a 10.5 heat range-we are at full throttle for 90% of the time therefore the engine is under a lot of load and a cooler plug performs better.
if your bike is fouling with an 8 and you put in a 9,it will be worse.
Some bikes need resistors to help the coil to function correctly,they will either have the in the lead,or they have plugs with them fitted.See what the manufacturer says and use the recommended stuff.
If you had a leak in the cooling system,the water would come out-not air coming in.The waterpump may well be damaged-these are usually plastic and quite prone to fail.
:done:

[MrMelon]

ok, so I just got a call from the workshop, and he reckons that it's losing coolant, but there are no leaks externally anywhere, and the head gasket definately isn't blown, so he reckons that it's got a cracked barrel that the coolant's leaking through there..

So I took it into him 3 weeks ago telling him it was overheating and suspected it was blown head gasket because it was losing coolant, so he charged me $400, replaced the head gaskets and didn't fix the fucking overheating problem at all.

Reckon's it's going to cost $3-500 to pull the barrels off and check them out... this is bullshit.

 

[Dave]

your right, it seems as though they have miss diagnosed your problems.If you were in auckland i would say come in and see me and lets get the thing figured out.It could be that the head gaskets weren't done properly,or that the coolant is leaking into the crankcase between the cases,or into the gearbox through the internal waterpump seal. Either way i wouldn't trust the people that you used before.-you've mentioned missing-That would indicate that the water is ending up in the camber-so suspect crank case sealing or headgasket.
Cracked cylinders? really whats more likely to leak-a rubber seal, some silicone sealant? or an aluminium cylinder with crome plating right up the inside?-i'd look at the seals etc. first.

[MrMelon]

Well he's got it in there and reckons he was taking the barrels off it today to inspect them and see if he could find a crack.. He's going to pull it all apart and probably have to replace the head gaskets again anyway, so i'm going to try and argue that he should have tested it last week to make sure the head gaskets were actually the problem instad of just replacing them and charging me $400 for the pleasure. So at least the labour component for the last bill should be taken off this one.

[Dave]

good luck,its never a fun thing getting into disputes like this.
If he's an MTA member and it starts getting too much for you, they have a mediation service you can use.

[MrMelon]

Yeah i've documented everything from the start till now, and it definately feels like he's giving me the big shaft.

I'm having a talk to a couple of other mechanics and a lawyer about what to do.

All of the other mechanics seem to think there are a bunch of fairly simple tests that can be done to see whether it is actually a cracked head gasket/barrel/whatever without actually tearing the whole lot apart twice.

Fuckit I need to learn how to fix my own bike.. any tips on where to start learning about 2 stroke repair/maintenance? :D

[Motu]

Cooling systems can be a mine field - he could have fixed a blown headgasket,but uncovered another problem with the same symtoms,like a cracked barrel,sad,but a common senario.

When I do some work on a badly neglected cooling system I often tell the customer we may have started on a process whereby every part of his cooling system will have to be replaced,and posibly even a head gasket.Makes us look like a bunch of dickheads if it keeps overheating every couple of weeks,but someone has to pay for the previous owners neglect.Often a simple flush job results in a blown headgasket - sorry,but not my fault.

[matthewt]

Originally posted by MrMelon
and it definately feels like he's giving me the big shaft.

Can I ask what shop is doing the work ??

[MrMelon]

Well he's got it apart and looks like the barrels are fine but the base gasket is leaking... so a replacement one's going in and we'll see if that fixes it up.

[MrMelon]

Omg they're fucking hopeless. The base gasket they ordered in is the wrong one AGAIN! and he gave me the option of them keeping the bike in there for another few weeks over xmas when I was going to take it away, or them making up a base gasket which he said "should get the bike back on the road for a little while" But wouldn't tell me how long a little while was.

This shop is a fucking joke.
Do not deal with Richards Motorcycle Services unless your life depends on it.

[Dave]

Someone like RB Imports should be able to get your gaskets here in about 3 days from OZ.http://www.rbimports.com.au/

[curious george]

What about motomail? and do it yourself?
Have a look at www.rgv250.co.uk have some useful guides and links.
Buy a torque wrench if you are gonna do gasket stuff yourself.
If you have a camera, you could post pictures, and the online pannel of experts can help out!!!

[What?]

and do it yourself?
Buy a torque wrench if you are gonna do gasket stuff yourself.
Dead right. Also buy a manual and a ring compression tool (not expensive). Top end work on 2-strokes, even water cooled, is not difficult.

[MrMelon]

There's no english manual for my bike, but The japanese one I've got has some useful diagrams in it.

I'll definately be doing my own work on it next time.

[Dave]

Dead right. Also buy a manual and a ring compression tool (not expensive). Top end work on 2-strokes, even water cooled, is not difficult.
-Might want to save your money on a ring compressor-2 stroke pistons go in from the bottom-so you wouldn't be able to get the tool out if you did use one!

[gpercivl]

I just cut a piece of smooth plastic about 30mm wide and long enough to go 'round the piston from the side of a 2 litre 'coke' bottle or similar. Just wrap it round the piston and rings and tape it together with duct tape. This will then allow the piston to slide up into the cylinder with rings compressed, once all rings are in, just release the duct tape and pull out the plastic...I've done heaps of 4 cylinder (can do all 4 cylinders at once) bikes like this...cheap and easy with materials readily available.

In fact I'll be doing it again this weekend as I ran the big end bearing on #4 cylinder last weekend at Manfeild (due to over-revving :doh: )

[MrMelon]

Cheers dave, I've got the bits coming in from RB Imports.. they seem to think they'll arrive on the 23rd, so here's hoping I'll get the bike back for xmas :D

[What?]

-Might want to save your money on a ring compressor-2 stroke pistons go in from the bottom-so you wouldn't be able to get the tool out if you did use one!
:Oops:
But I have seen one (years ago) which is a metal version of what gpercival describes. Don't own one, though :( I have always tortured my fingers...

[Kickaha]

Interesting bike the 3XV as it shares a few of the same parts with the V-twin TZ250 GP bike and stuff like barrels and heads are a bolt on fit.

Top end work on these motors is very simple and if anything like the GP bike can be done in the frame,I have seen problems with the water pump impellers and shaft that drives them,but these seem to be fairly rare,but might also be worth checking.